Water-cooled furnace wall



Aug. '21, 1928.

A. B. HELBEG WATER COOLED FURNACE WALL Filed May 18, 1925 5 Sheets-Sheet1 INYENTUR Allin fielz'r ly ATTORNEY? Aug. 21, 1928.

A. B. HELBIG WATER COOLED FURNACE WALL Filed May 18, 1925 5 Sheets-Sheet2 OOOOO0000000000OOOOO OOOOOOOOOOOOOOOOOOO WATER COOLED FURNACE WALL k gZ2 Z2 INyENTOR 322m Bhezhy Patented Aug. 21, 1928.

UNITED STATES ALBIN BERTHOLD HELBIG, OF BERLIN, GERMANY.

WATER-COOKED Application filed May 18, 1925, Serial N o.

This invention relates to water cooled furnace walls, and has for itsprimary object to provide a furnace wall structure of this characterwhereby rapid deterioration of the wall by the intense heat will beprevented. The present improvements generally comprehend a fire brickwall for furnaces of that general type in which cooling tubes areprovided in the interior of the wall." It has heretofore been generallysupposed to be impossible to build such a furnace wall which will besufficiently elastic to allow the proper and necessary expansion andtherefore, since such large areas of the brick work are exposed to theradiation of the fire, it has been found necessary infurnaces of moderndesign to provide numerous expansion joints in such furnace walls. Withmy present improvements however, I provide a wall that is in effect ahomogenous structure, no mortar joints being provided. At the same timethe new wall structure is exceedingly simple and may be easily erectedat minimum expense. It is also quite elastic and insensible tovariations of temperature.

It is another object of my invention to provide a firebrick wall forfurnaces of the above character, which under working conditions will beabsolutely gas proof and will at all times retain its original position.

With the above and other objects in view, the invention consists in theimproved furnace wall structure and in the form, construction andrelative arrangement of the several 85 parts as will be hereinafter morefully described, illustrated in the accompanying drawings, andsubsequently incorporated in the subjoined claims.

In the drawings, wherein I have illustrated several simple and practicalembodiments of the invention. and in which similar reference charactersdesignate corresponding parts throughout the several views,-

Figure 1 is a'transverse section through a 46 portion of the furnacewall;

Fig 2 is a front elevation:

Fig. 3 is a side elevation of the wall;

Figs. 4 and 5 illustrate the application of my resent improvements to aBabcock-Wil- 50 ox oiler, and

Figs. 6 and 7 illustrate another application of the invention to aStirling boiler.

The walls of the furnace structure are lined with or have incorporatedtherein, a multiplicity of spaced water tubes 1 which are properlyconnected to the boiler and to each runuaon WALL.

31,229, and in Germany January 10, 1925.

other. These water tubes serve first to cool the refractory firebrickand maintain the same at a temperature below the fusing point, quicklycarrying away the heat radiated into these brick, and secondly saidtubes serve as supports for the wall structure, and by means thereof itis possible to appreciably reduce the thickness of the wall withoutseriously affecting its stability.

Between the several tubes, the firebricks 2 are inserted, there beingsufiicient play to allow for expansion. Preferably the bricks are madeas small as possible so that the heat radiated to them from the firewill be very quickly transmitted to the boiler. Some of these bricks areprovided with a transversely extending opening therethrough for a rod 3.A fastening screw 4 is connected to each end of this rod and imbedded inthe fi'rebrick. As will be seen from reference to Fig. 3 of thedrawings, each brick is provided on its top and bottom with transverseshoulders and the adjacent brick between the tubes 1 are arranged inreverse position so that the shoulders of each brick will engage theshoulders of the bricks above and below it. The bricks thus rest evenlyupon one another. .It will also seen by reference to Fig. 1 of thedrawings, that each brick has a relatively wide portion extending at itsopposite sides parinsulating material 6 applied thereon and does notincrease during the heating of the brick. The brick 2 are directlyheated from the furnace fire and are therefore, of a higher temperaturethan the brick 5 which are only indirectly heated through contact withthe brick 2. This difference in temperature of the bricks is compensatedfor by the elasticity of the insulating material 6. Thus, the wall isrelieved of all strains and stresses which might otherwise be caused byexpansion of the wall brick due to high temperatures. Owing to thebreaking of the joints between the bricks 2. these joints are moreeffectively caulked or sealed by the insulating material 0.

By inspection of Fig. lit will be seen that the bricks 2 project to bothsides of the water pipes 1 these brick having relatively wide ends whichextend partly around and partly overlap the pipes 2 and the faces ofthese relatively wide ends make up the inner or furnace side of the wallbuilt with. these bricks. The wide ends of the bricks have slight spacesbetween them going in as far as the pipes 1. The relatively narrow bodyof each of these bricks passes between the pipes l in the 0ppositedirection and the extremities covered by the insulating material 6 andplate 7 make up the outer side of the furnace; the bricks 5 being placedbetween the pipes 1 and insulation 6; and the insulation 6 and plate 7being held fast by the attaching elements 4. The plate 7 when engaged bythe attaching means 4 serves as a means for uniting the bricks together.

By clamping the wall bricks against the water tubes in the manner aboveexplained, the lower bricks are partially relieved of the weight of thewall structure and the bricks are very efficiently cooled so that theywill retain their physical qualities and their resistance to stress orstrain.

In Figs. 4 to 7 inclusive, I have shown the side and top walls of thefurnace chambers provided with air chambers 9. IVhilc the heat is wellretained within the furnace chamher by the walls, some of it may passthrough the wall structure into these air chambers. From the airchambers the heated air is discharged into the furnace and may be usedalternately as primary and secondary air.

In Figs. 4 and 5 I have illustrated the present improvements as appliedto a Bahcock-Wilcox boiler generally indicated at 10.

The mixture of primary air and coal is introdnced to the furnace chamberthrough the front wall 1]. and said wall is perforated or provided withopenings through which air is forced under pressure into the combustionstream from the air chamber 12. The air in this chamber serves to coolthe wall structure. The upper portion of the furnace is occupied mostlyby the boiler tubes and therefore. only a relatively small part as at13. must be water cooled which is also the case with the other threesides and the bottom of the furnace. In this type of furnace. watertubes are elevated above the bottom thereof to form a water screen 14from beneath which the ashes are removed mechanically in granulatedform.

In Figs. 6 and 7 of the drawings I have shown the application of mypresent improvemenses ments to a Stirling boiler indicated generally at15, this installation being practically the same as that above referredto, with the exception that the water tubes are imbedded in the bottomwall of the furnace which is elevated so that: the residue or ashes maybe withdrawn in a liquid condition.

IVhilc I have above described an embodiment of'the invention which hasbeen found very satisfactory in practical use. it will nevertheless beunderstood that the several features thereof may also be incorporated invarious other alternative structures. and I accordingly reserve thep'rivilege of adopting all such legitimate changes as may be fairlyembodied within the spirit and s ope of the invention as claimed.

I claim:

1. In a wall structure for furnaces. spaced water tubes. firebrickarranged between said tubes and projecting from opposite sides thereof.said firebrick provided on their opposite side faces with horizontalshoulders for interlocking engagement with each other. additionallirebrick arranged upon one side of said tubes between said first-namedfirebrick. an elastic insulating sheet covering the outer face of thewall structure, a plate engaged upon said insulating sheet. andfastening devices connected with certain of the firstnamed bricks andextending through said insulating sheet and the plate and therebyuniting the bricks in assembled relation while permitting of theirrelative expansion under heat.

2. In a wall structure for furnaces. a plurality of water tubes,firebricks between the tubes in contact with one another and projectingbeyond the tubes at both ends. additional fire-bricks placed between thefirst named bricks. the latter having enlarged extremities partlyoverlapping the tubes on the furnace side of the wall; the outer ends ofsome of the first named bricks having attaching elements. and meansextending over the outer face of the wall and engaged by said attachingelements to hold said bricks in assembled relation.

3. In a wall for furnaces. a row of water tubes. lirebricks between saidtubes. arranged in contact 'with one another. said tirebricks havingshoulders for engagement with each other. additional fircbricks betweenthe first named bricks and engaging one side of said tubes. said firstnamed bricks being shaped to bind against the tubes adjacent their endson the furnacesidc of the wall. and projecting at both ends from saidrow of tubes. some of said first named bricks having attaching elementsand means upon the outside of the wall and secured by said attachingelements to retain the bricks in position.

4. In a wall for furnaces. a row of water pipes. lircbricks between saidpipes arranged in contact with one another, said bricks havingrelatively narrow'portions extendin beyond the pipes toward the outerface 0 the wall, and relatively wide ends part-1y overlapping said pipeson the furnace side of the wall, additional bricks between the narrowportions of the first named bricks, some of the first named brickscarrying fastening elements, elastic material over the outer side ofsaid wall, and a plate covering the elastic material and secured by saidfastening elements.

5. In a wall for furnaces, a plurality of water pipes, firebricksbetween said pipes and arranged in contact with one another, saidfirebricks extending beyond the pipes at both ends, said firehrickshaving their ends on the furnace side of said wall enlarged and partlyoverlapping said pipes, the enlarged ends having spaces between them toexpose parts of said pipes, the remaining portions of said bricks beingrelatively narrow and extending between the pipes in the oppositedirection toward the outer side of the wall. additional bricks betweenthe first-named bricks and engaging said tubes and lying between sameand the opposite or outer side of said wall, elastic material arrangedover the outer side of the wall, fastening elements carried by some ofsaid first named bricks, and a rigidplate over said elastic materialsecured by said elements.

6. In a wall for furnaces a row of water pipes, firebricks bet-ween thepipes arranged in contact with one another and extendlng at both sidesof said row, said bricks having their ends on the furnace side of thewall shaped to bind against the pipes, said ends being spaced apart toexpose portions of said pipes, additional firebricks between the firstnamed bricks and abutting the pipes, elastic material engaging saidadditional bricks and the first named bricks on the outer side of saidwall, certain of said first named bricks carrying fastening elements,and a ,plate covering the elastic material and secured by said fasteningelements.

In testimony that I claim the foregoing as my invention, I have signedmyname hereto.

ALBIN BERTHOLD HELBIG.

